Computers as a rule have several hardware interfaces, for example USB (universal serial bus) connections or Firewire connections, that allow peripheral devices to be connected to a computer via cables. The aforementioned hardware interfaces are found as a rule on the back or front of a computer, or, in particular with laptops, on their narrow lateral surface.
A connection according to the USB standard is distinguished in that it is designed to supply a connected peripheral device with power via a standard-gauge USB cable and/or to exchange data with it. For this purpose, voltage of +5 volts and a maximum current strength of 500 mA are provided by a USB connection. A standard-gauge USB cable has four power wires running through it, each of which is connected in a plug with contacts so that it is electrically conductive. The electrical data transmission in the standard-gauge USB cable proceeds here over two wires, one of which transmits the data signal and the other the signal that is inverted in relation to it. Two additional wires serve to power the connected peripheral device. If a peripheral device has a higher power requirement (>500 mA) than can be covered by a single standard-gauge USB cable, then it needs an additional power supply or its own power supply, in particular in the form of a power adapter, that is connected to a power outlet and delivers electrical energy to the peripheral device from the power grid.
Electric cables that can be used to connect two devices are known, for example, from patents DE 202005009 995 U1, DE 202006002937 U1, DE 10013247 A1, U.S. Pat. No. 6,663,420 B1, US 2003/0228791 A1, and U.S. Pat. No. 5,573,425. The aforementioned prior art refers to electrical cables that serve to connect a computer (PC) with peripheral devices such as a mobile telephone or external hard drive. Devices connected by these cables are distinguished either by a comparatively low energy demand and/or in that only small data quantities can be transmitted via these electrical cables. In the event that a peripheral device requires more energy, additional power supply is necessary by using a power adapter.
For a number of endoscopic applications, digital image transmission systems are employed such as, for example, the autoclavable endoscopic IMAGE 1 digital video camera from Karl Storz. With the help of such a camera and an endoscope, minimally invasive procedures can be performed in an operating room, such as visual inspection of internal organs or the removal of tissue samples. Similar image transmission systems are available for industrial endoscopy to be able to inspect technical equipment. With endoscopes of this type, inspections are then possible, for example inside an airplane engine, without dismantling it. Once the defective or worn-out part has been found in the airplane engine, it can then be dismantled with precision and consequently can be repaired economically and quickly.
The aforementioned image transmission systems are distinguished by an increased energy requirement and the large amounts of image data to be transmitted. Here the power supply of the endoscopic video camera as well as the image information generated during use, for display on an image screen or for transfer to a separate database, is simultaneously provided by a single cable intended for power and data transmission. This cable, on its two free ends, is distinguished by a complex, special multi-polar plug that is designed to make the cable connection with a control unit with database, for example the Image 1 hub HD from Karl Storz.